During the process of drilling and completing a well it is necessary to run or pull the pipe into or out of the wellbore. When one section of pipe is removed from the top drive or kelly, mud which is located above the pipe being removed will spill on the rig floor or into the environment. Mud saver valves are available and are in use for the purpose of preventing such spillage. These valves have at least one seat, which is firmly attached to a rigid portion of the valve system. The second seat is firmly guided into contact with the first seat such that if the seats are not perfectly aligned there will be a leak path between them. In practice these devices seldom form a perfect seal and will allow mud to leak onto the rig floor or into the environment. Such an example is disclosed in a Product Bulletin titled “Mud Saver Valve” from Smith Services, a business unit of Smith International.
Accordingly, it is an object of the present invention to provide a mud saver valve having a seat with at least one seat allowed to float allowing the seats to self align when forced together over their entire surface to prevent leakage of fluid. It is recognized that both seats could be allowed to float further assuring alignment of the sealing faces to provide a seal.